Who’s responsible?

“It's Corday and Greene's wedding day, but - amid a heavy rain that shows no sign of letting up - they seem to be encountering nothing but trouble in getting to the church on time. Things begin on a sentimental note as Corday's mother (Judy Parfitt) presents her with earrings that have been in the family for three generations. Then Greene (Anthony Edwards) realizes that he left his wallet at the hospital, and his trip to retrieve it becomes a series of misadventures that includes his car being towed. Corday (Alex Kingston) has her own auto difficulties - the limousine service knows nothing about arrangements to pick her up. In another storyline, the ER staff deals with injuries caused by an overturned prison van. Charles Corday: Paul Freeman.”

Paul Freeman? Why does that name sound familiar?

Here’s a hint: “You and I are very much alike. Archeology is our religion, yet we have both fallen from the pure faith. Our methods have not differed as much as you pretend. I am but a shadowy reflection of you. It would take only a nudge to make you like me. To push you out of the light.”

Ah! Does Freeman’s face melt off when he enters the church?

No.

What’s TV Guide not telling us?

The prison van is full of women. Greene spends a hunk of the episode with Benton. As Mark grows tardier, Lizzy worries the worries of a woman about to marry a brain-cancer survivor.

Prison van? Tell us there’s more gunfire!

Nope, just an attempted escape.

Who’s holding down the ER while Greene gets married?

Jing-Mei.

Chen is back? What’s she up to?

She treats a boy stricken with hypothermia when his divorcing parents forget to pick him up from soccer practice. When the kid’s father tells Jing-Mei they haven’t yet told the boy abou the divorce, Jing-Mei admonishes: “That doesn’t mean you can forget about him.” Chen is later seen pining for the baby she herself gave up for adoption.

Where’s Weaver?

Following her campaign to suspend Mark’s license, Kerry was not invited to the wedding and obviously feels horrible about it. When her flight to a conference to Las Vegas is delayed, she attracts a fellow (male) traveler at O’Hare!

Is she smitten?

Well, he is! He invites Dr. Weaver to future dinner, and gives her his card.

Does this mean Kerry is switching teams again?

Not necessarily. After a slight hesitation, she trashes the guy’s card the minute he dashes for his flight.

Is Cleo back?

Yes. And she’s none too excited about attending the wedding of Peter’s ex-girlfriend.

Does Mallucci show?

Hauling a weighty gift, Dr. Dave is spotted outside the church.

Do John and Abby continue to converge?

Seemingly. But Abby is sick and John’s date for the wedding is his underage girlfriend, Rena.

What’s good?

”What? You didn’t think I’d be invited?” Romano is invited, and is also quick to poke fun when Mark doesn’t get to the church on time. God and man.

I knew I recognized him from something...thanks for the info!
BTW, the highlights from ER:
Woman on the bus telling Greene that cell phones give you brain cancer. Priceless!
Romano and Elizabeth's mother meeting again: the last time I saw you were operating on a dog comment. Great.
Romano revealing that he is a human for about a minute (in front of Elizabeth's parents even): BTW, these glimpses are effective if used very sparingly.